Home networking is a key technology for the evolving home infotainment market, and it is expected to become a very large market by itself within the next decade. Home networks will connect between computing devices (personal computers, palm computers, network computers, etc.), entertainment devices (TV, VCR, DVD player, video camera, audio systems, etc.), I/O devices (printer, scanner, head- sets, keyboards, remote controls, mouse, loud-speakers, etc.), home appliances, and modems (such as cable modems, DSL modems, and PSTN modems) that connect the home outside. The home network will enable a wide range of application such as internet sharing, peripheral sharing, file and application sharing, and home automation. The home network will distribute the computation power of the computer from the study room to the living rooms.
There are several home networking solutions that have already been proposed, including networking over the existing telephone wiring (e.g. HomePNA), networking over the existing power lines, short range wireless networks (Bluetooth), medium range wireless networks (e.g. HomeRF, IEEE802.11), and solutions that require new wiring, such as IEEE1394 (I.LINK) or CAT 5 Ethernet wiring.
Existing Telephone wiring (HomePNA) generally allows ordinary voice telephone calls to be carried over the wire, while at the same time providing up to several megabits of data throughput.
It is also possible to use the normal AC electrical wiring in the home for data transmission. Electrical wiring has been used in the past for low bit-rate data applications (e.g. home automation). Technologies for achieving multi megabit throughput on existing residential electrical wiring are under investigation in the industry.
Wireless technologies (Short-range wireless; Bluetooth; HomeRF; IEEE 802.11) provide several megabits of throughput; however, their effectiveness can vary, depending on the size of the house, the proximity of other wireless networks, and other sources of noise.
The IEEE 1394 (i.LINK) standard defines a serial interface between digital devices. This inexpensive, easy-to-use and high-speed bus handles multimedia bandwidth requirements and provides a universal interface for a variety of devices. By allowing seamless data exchange between devices such as workstations, personal computers and digital televisions, VCRs, camcorders and set-top boxes, it enables a. new generation of computers and consumer electronic devices to operate in a common environment.
Originally developed as an interface to replace SCSI, IEEE 1394 offers bi-directionality, high data transfer rates and isochronous data transfers. This fire-wire technology required special wires.
For new homes, it is anticipated that standard Category 5 wiring can supplement twisted-pair telephone wiring. The added cost of including this extra wiring is low and the benefits reaped can be great, because 100BaseT and other high-speed network types work well over this cable.
TV wiring that consist of coaxial cables are used to connect the antenna/cable TV output, typically via passive splitters, to the cable outlets at specific points in the home. Typical home TV wiring scenarios are depicted in FIG. 1.
The signals transmitted over the in-home coaxial TV wiring may include regular video channels, data channels for fast Internet access (using e.g., DOCSIS cable modem), voice channels for telephony over cable, pay-per-view, control signals and more.
Technically, to use the in-home TV wiring for home networking applications, one may connect standard cable modems through the cable TV (CATV) system. Data from one cable modem can be transmitted to the other cable modem via the CATV head-end.
Such a configuration has several drawbacks: (1) it loads the system, possibly above the typical headend system capacity; and (2) it introduces large delays that cannot be tolerated by at least some of the applications. Therefore, it is unlikely that cable operators will adopt such configuration.
It should be noted that a cable modem could be used to connect any type of home networking system to external (out of the home) networks, such as the Internet.
A home networking solution may also be built at a home that does not connect to the cable infrastructure (i.e. a home that is connected to a standard home antenna, a satellite dish, another access network (xDSL), or a wireless local loop).